Officials say the measures will pay for themselves by preventing thousands of cases of diabetes.

So far more than 150,000 patients have been referred for courses, with men making up around half of participants.

Today Mr Stevens will tell Diabetes UK’s annual conference that the controversial programme is reaping rewards, and said NHS efforts to tackle obesity were also showing promise.

“The NHS is already leading the way in the battle against the obesity crisis by slashing the sale of sugary drinks and super-sized snacks in hospitals, and the results now coming out of our diabetes prevention programme are also positive,” he will say.